In recent years, there has been significant growth in wireless technology being used to control mains powered appliances, lighting systems and building heating and cooling. These systems are normally installed in large buildings and provide efficient control of the entire local environment.
The proliferation of domestic wireless networks for connecting computers to the Internet and sharing peripherals such as modems, printers, etc., has created a ready-made framework for wireless home automation. In most cases these networks use wireless technology that conforms to the Wi-Fi Alliance specifications and is generally known as “Wi-Fi.” More specialized systems use proprietary networks outside of general Wi-Fi architecture and conform to specifications such as Zigbee or others. In essence the network arrangements are similar, but not compatible.
Conventional Wi-Fi networks are typically based on the presence of a specific control device known as a wireless Access Point. These devices provide physical support for the wireless network, perform bridging and routing between devices on the network, and allow devices to be added or removed from the network. A typical home Wi-Fi network usually includes a wired connection to the telephone Wide Area Network (WAN) for broadband internet services, with a number of computers, printers, tablets, smartphones, and similar devices connected wirelessly to the Access Point. The connected devices do not communicate directly with each other, but do so through the Access Point that acts as a gateway for all communications.
It can be appreciated that home automation based on a Wi-Fi network requires the provision of a wireless Access Point and a user interface device such as a PC for even the most basic system. Because all communications have to pass through the network's Access Point, if it becomes disabled for any reason, the entire home automation system fails. If there are other high traffic devices attached, the Access Point can also become overloaded to the point that data latency inhibits the home automation functions.